Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number HX55 6580 found under Filter Air Au Iliar by United Specialties Co. The National Stock Number assigned to this part is 2940006958797, and the Federal Supply Class is 2940 Engine Air And Oil Filters Strainers And Cleaners Nonaircraft. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like HX55 6580.